The slope of the top graph (height vs. age) is increasingly positive while the slope of the bottom graph (growth rate vs. age) is negative. The slope of a tangent line at any given point on the top graph is greater and also positive, while the slope of a tangent line on the bottom graph is negative or a very low positive number. From the ages of 5-10 on the top graph, the minimum and maximum were at 1.042 at 5 (min) and 1.396 at 10 (max). After an integral was taken of the bottom graph, the shaded area represents how much he was growing from age 5 to 10. The shaded area is about equal to the value given when subtracting the minimum from the top graph from the maximum. At age 3 he was about half as tall as he grew to be when he reached his peak height at age 20. The generalization made in the introduction was correct and does apply. The most rapid growth was when he was 0-10 years old. As he got older into his teens he began leveling off.
The Growth of Colin